Arithmetical calculator



No. 614,849." Patented Nov. 29, I898. W. A. DRAKE.

ARITHMETICAL CALCULATOR.

4 shaets sheet (No Model.)

Patented Nov. 29, I898.

W. A. DRAKE.

ARITHMETIOAL CALCULATOR.

(Application filed Nov. 8, 1897) 4 Sheets-Sheet 4.

(No Model.)

THE NORRIS wrans c wuoruumon WASHINGTON. n. c,

' UNITED STATES PATENT OFFICE.

\VARREN A. DRAKE, OF CHICAGO, ILLINOIS.

ARITH METICAL CALCU LATO R.

SPECIFICATION forming part of Letters Patent No. 614,849, dated November 29, 1898.

Application filed November 8, 1897.

To all whom it may concern.-

Be it known that I, WARREN A. DRAKE, of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Arithmetical Calculators, of which the following is a specification.

The object of this invention is to simplify arithmetical calculations, particularly those which involve the calculation of percentages upon numerous amounts varying in size and such as may be expressed by one or more significant figures and one or more ciphers annexed thereto.

In carrying out myinvention I make use of certain instrnmentalities, consisting, essentially, of tables of figures and a decimal-bar, said tables and said bar having relative movement whereby any transverse line or row of figures may be brought into juxtaposition to the bar and whereby also the points or indicators of the decimal-bar may be varied with relation to the figures or characters in such transverse row and the number expressed by said figures may be multiplied or divided-that is to say, increased or diminished in a tenfold ratio.

In a companion application, filed of even date herewith and bearing Serial No. 657,780, I have explained a simple apparatus for use in making calculations of this kind and have therein described and shown means for moving the table and the bar relatively to each other. The capacity of said apparatus is somewhat limited, owing to the fact that in the preferred form of construction the tables are mounted upon the periphery of a revolving cylinder, by the rotation of which a line or row of figures is brought into position with relation to a sight-opening and to the decimal-bar.

My present invention has for its leading object the provision of an apparatus of such capacity that a much larger number of arithmetical calculations may be made without unduly increasing the size of the apparatus.

To this end my invention consists in the combination, with the decimal-bar, of a series of holders or carriers for the tables, preferably in the form of cylinders, said cylinders being so arranged as to receive and present an extended table, sections of which are mounted upon the several cylinders, the lat- Serial No 657,779 (No model.)

ter being so arranged as to be brought into convenient relation to the sight-opening and decimal-bar in making the computations.

In the accompanying drawings, Figure 1 is a front elevation of said apparatus; Fig. 2, an end elevation. Fig. 3 is a longitudinal sectional elevation through the casing and showing some of the interior parts in broken elevation. Fig. 4 is an end elevation with the casing removed and a part of the supportingframework and an exterior cylinder brokenaway. Fig. 5 is a detail of the locking-bolt.

In the drawings let 10 represent the body of the casing, and 11 a hinged lid or cover therefor. At its front the body is provided with a shelf 12, on which is mounted to slide in suitable ways a decimal-bar 13, the latter being slotted, as at 14, and guide pins or screws 15 being passed through said slots into the substance of the shelf. The bar 13 is provided with a series of pointers 16one for each column of figures to be operated uponand to its end is secured an operating-lever 17, pivoted as at 18, and the end below the pivot being engaged by an operating-screw 19, provided with a milled head 20. The front edge of the lid carries a plate 21, whereon may be marked appropriate headings corresponding to the headings of the items of calculation. Mounted upon suitable trunnions having bearings in the end walls of said casing is an external cylinder or shell 22, having slots parallel to its axis equidistant from each other to afford sight-openings for certain internal cylinders hereinafter to be described. One of said slots is shown in the broken section at 23, Fig. 4. On the periphery of said cylinder in the spaces between said slots may be mounted a table or tables formed by printing numbers in columns and rows on paper or other suitable material and affixing it to the surface of the cylinder, the tables being interrupted, of course, at the slots. Each section of a cylinder twelve inches in diameter and ten to twelve inches in length will contain ten columns of numbers of seven figures each upon an average and eighty-four lines or rows of said numbers, all printed in large type,'so as to be easily read, and by the use of smaller type the capacity of the cylinder may be greatly increased, while still preservin g legibility. Obviously also the size'of this cylinder may be varied; but in order to obviate the necessity of making this cylinder of inconvenient size I have made the same hollow and have mounted therein smaller cylinders, as indicated in Fig. 4t. As there shown, four of these cylinders are employed, (marked, respectively, 24, 25, 26, and 27,) each of them being journaled in the arms of the spiders or heads 28, which are secured with the ends of the exterior cylinder. One of the trunnions, 29, of the exterior cylinder is hollow, and a shaft 30 passes through the hollow of said trunnion and is provided with a gear-wheel 31, enmeshed with the gears 32 on the trunnions of the smaller cylinders. The hollow trunnion 29 has an operating-wheel 34:, and the shaft 30 has an operating-wheel 35. Thus by turning the hand-wheel 34 the larger or exterior cylinder 22 may be turned, so as to bring any row of numbers on the face thereof into position adjacent to the decimal-bar, the smaller and interior cylinders, of course, being carried around with it. On said interior cylinders additional tables or sections of the same table as that carried by the exterior cylinder may be placed. Thus an apparatus having its largest cylinder of the dimensions above given may be made to show any number between 1 and 99,900,000 which does not contain more than three sucees sive significant figures. For convenience let it be assumed that the outer cylinder contains in the left hand column the numbers from 1 to 378, inclusive, with five ciphers following each of said numbers. Obviously, therefore, by shifting the decimalpoint (which will be assumed to follow the last significant figure) to the right the number expressed by said significant figure may be multiplied tenfold, and by successive removals of the decimal-point to include additional ciphers these multiplications may be extended one hundredfold, one thousandfold, ten thousandfold, the. and therefore the number 37,800,000 may be expressed by shifting the decimal'bar with reference to the last number on the external cylinder. To carry the calculation further, let one of the smaller or internal cylinders be provided with a table having numbers similarly arranged from 3'79 to inclusive, another with the table running from 585 to 689, another from 091 to 8&5, both inclusive, and the fourth cylinder from 8-10 to 999, both inclusive. Now if it be desired to expose any row of numbers on any one of the internal cylinders the larger cylinder will be turned around until the slot therein over the desired internal cylinder is brought into juxtaposition with the decimal-bar, and then by manipulating the hand-wheel 35 said cylinder may be turned to bring any number thereon opposite the sight-opening.

In arranging the tables I preferably dispense with all numbers ending in a cipher, such as 20, 80, &e., as by shifting the decimal-bar the value of any number maybe increased or diminished tenfold, and there fore 20, 30, &c., maybe produced from the figures 2, 3, &c., by moving the decimal-bar one place to the right. In order to lock the outer cylinder in position for the manipulation of any one of the internal cylinders, I provide a locking mechanism, as shown in Figs. 3 and 5. Said locking mechanism consists of a locking-bolt 30, mounted to slide in the end wall of the casing and adapted to enter apertures 37 in the head or spider of the exterior cylinder. A pivoted lever 38 is connected to this bolt, and the latter is normally thrust into engagement with the outer cylinder by the leaf-spring 39. The bolt is withdrawn by pushing in the pin 40, pivoted to the upper end of the lever 38, and it may be locked in the released position by means of the spring-catch 41, so as to leave the large cylinder free to revolve. The numbers or sections of the table carried by each of the interior cylinders may be indicated on disks or buttons, as 42, mounted upon the wheel 43, carried by the trunnion of the larger cylinder at the opposite end of the apparatus from the hand-wheels 31- 85, or said disks or buttons might be placed upon the hand-wheel 34:-

Let it be assumed that the apparatus is to be employed for tending tax es. The tables would then be made up with appropriate headings to indicate the valuation of the property, the different items of taxation, and the total amount of tax. The unit of taxation being one dollar, the amount to be raised is calculated by taking a certain percentage of one dollar for each of the items, such percentage constituting the rate. Applying this rate to the unit the amount of tax for each specific purpose upon one dollar is ascertained and extended in line with said unit under appropriate headings and the total tax on one dollar indicated in the column at the extreme right. The table is continued by doubling these amounts for two dollars, and so on throughout.

The economy of the apparatus resides in the fact that by simply turning the cylinders, so as to present any given number representing the valuation or a number the first significant figures of which correspond either substantially or exactly with the number expressing the valuation of the property, the different items are displayed and may be written out without the tedious and repeated multiplications and additions necessary to find the amount of tax for a single item and without returning to these tables for each specific item. Thus in the illustration shown in Fig.1 under the head of Valu ation appear the significant figures 505, followed by five ciphers and the decimal in such position that the decimal-point indicates the correct reading of the number,as 5,050,000. Assuming the table to have been extended on the basis of of one percent, then the State tax would be twenty-seven thousand seven hundred and IIO seventy-five dollars; the county tax would be thirty-nine thousand and eighty-seven dollars town, two thousand and twenty dollars; city, one hundred and twenty-three thousand seven hundred and twenty-five dollars, and so on,the total tax appearing as fou r hundred and twenty-one thousand three hundred and seventy-two dollars. Now suppose that instead of five million five hundred thousand dollars the amount of tax was required upon live hundred and five thousand dollars, the decimal-bar would be moved one point to the left. If moved an additional point, the valuation would reac $550,500. If the valuation were five hundred and five dollars, the decimalpoint would be moved to the third place from the left and the numbers under the respective headings would be diminished in the same ratio. By means of the plurality of rollers, therefore, the capacity of the calculator is very largely increased and arithmetical calculations may be made by its aid to any reasonable or probable amount without making the apparatus of such size as to be inconvenient in operation.

While I have shown the apparatus provided with four internal cylinders, it will be understood that a smaller or larger number may be employed, depending upon the requirements of the apparatus; but obviously as many interior cylinders may be employed as can be operatively mounted within the outer cylinder without thereby increasing the external dimensions of the machine or apparatus, and obviously also the principle of the in- .vention may be further extended by mounting smaller cylinders within the interior cylinders described, and the number of such added cylinders may also be varied.

While I have given the dimensions of the external cylinder and its capacity, I desire it to be understood that such dimensions and capacity may be considerably varied while still preserving the utility of the apparatus. Furthermore, the principal feature of my inventionthat is to say, the employment of a plurality of rotatable supportsmay be employed in an apparatus where the external cylinder shown is omitted and said plurality of cylinders may be employed in calculators adapted for other purposes than the extension of taxes.

I make no claim in the present application to the subject-matter of my other application of even date herewith, Serial No. 657 ,7 80, hereinbefore referred [0, wherein I have claimed in substance an arithmetical calculator comprising a movable backing or support having numbers arranged therein in columns and a decimal-bar having fixed pointers, said support and bar being capable of rela tive movement to increase or decrease the values expressed by the numbers on the backing or support; nor do I herein claim the subject-matter set forth in an application of even date herewith for Improvement in interest-calculators, bearing the Serial No. 657,781, wherein I claim in substance an interest-calculator comprising a suitable support having an interest-table thereon and a decimal-bar, said table and bar being relatively movable and the bar being provided with pointers having independent movement.

I claim 1. An arithmetical calculator, comprising in combination, a plurality of rotatablymounted cylinders or supports having numbers tabularly arranged thereon and a decimal-bar having pointers, said supports being independently rotatable upon their axes and severally movable with relation to the decimal-bar, whereby any number on either or any of the supports may be brought into j uxta position to the bar and the value thereof increased or diminished, substantially as described.

2. An arithmetical calculator, comprising in combination, a decimal-bar having pointers thereon, a plurality of rotatable supports each having numbers serially arranged in tabular form thereon, said supports being rotatable upon their own axes and bodily movable, substantially as described.

3. An arithmetical calculator comprising in combination, a decimal-bar having pointers thereon, a series of cylinders mounted upon axes parallel to said bar, each of said cylinders having depicted thereon a series of numbers in tabular form, said cylinders being mounted upon a suitable framework revolving upon an axis and each capable of independent rotation on its own axis,substantially as described.

4. An arithmetical calculator, comprising in combination,a decimal-bar having pointers thereon, a hollow external cylinder having a series of numbers depicted thereon in tabular form and provided with one or more transverse slots affording a sight-opening and one or more internal cylinders journaled upon and moving with said external cylinder and with its periphery adjacent to said slot and capable of rotation upon its own axis, substantially as described.

5. An arithmetical calculator comprising in combination, a suitable casing,-a sliding decimal-bar, an external cylinder capable of rotation about a fixed axis and a plurality of interior cylinders rotatably mounted within said external cylinder, suitable gearing for operating said cylinders and a locking mechanism for the external cylinder, substantially as described.

\VARREN A. DRAKE.

lVitnesses:

FREDERICK C. Goonwnv, S. T. MANN. 

